This invention relates to a method and apparatus for winding yarn strips draw from a bobbon creel on a warping drum.
With section warping machines, such as those known from the applicant's DE-A1-38 12 045 and DE-PS-25 10 517, a warping reed, together with a deflection roll or a press roll, is arranged on a warping carriage. When warping, numerous yarns are led through the warping reed and onto the warping drum around the deflection roll or press roll, whereby yarns in the form of a strip are in each case wound on to form a winding. At the same time, the first strip is wound onto the cone of the warping drum with a parallelogram shaped cross section. As soon as the first strip is wound on, the next strip is laid on the drum immediately next to the fully wound strip and, likewise, subsequently immediately wound on with the appropriate yarn length and parallelogram shaped cross sections. This procedure is repeated correspondingly with the strips which follow, until the entire yran warp has been wound onto the warping drum. For the winding procedure of each strip, the warping carriage must first of all be brought to a start position, from which it is continuously moved with regard to the growth of the strip and the inclination of the cone, in order to make the parallelogram shaped build-up possible. At the same time the press roll is pulled back with the increasing winding thickness, in order to keep the pressing force as constant as possible. In the case of known section warping machines of this type, a common drive for the warping carriage and the feed of the press roll is therefore provided, with which, out of necessity, the relationship between lateral carriage movement and feed of the press roll is mechanically determined. It is also known with such section warping machines that a reference winding is first of all produced on the warping drum, that the thickness of the reference winding, dependent on the number of rotations of the warping drum, is determined and accordingly the common feed of the warping carriage and press roll dependent on these measured values, is corrected. This kind of correction, however, only causes the enlargement or diminishment of both feed values (parallel and radial to the warping drum) without the angle arising from the simultaneous movement in the X- or Y-directions changing itself as a result. If, however, the direction of the warping carriage travel does not correspond exactly with the angle of the cone, the strips will not be uniformly wound. In practice, those problems are hardly avoidable, for reasons of tolerances in fabrication of the cone of the warping drum and of the drive mechanisms of the warping carriage and the press roll alone. In addition, the necessity of manufacturing the cone of the warping drum as exactly as possible arises from this, entailing a complicated construction and fabrication procedure.
It is the purpose of the invention to avoid these known disadvantages, and thus to create in particular a cone section warping machine and a method of warping which makes an exact and angularly true guide of the strip possible. In addition, the fabrication effort, in particular for the manufacture of the drum cone, should be made easier and the application of drums with varying cones--whether a result of fabrication tolerances or replacement--should be made possible . According to the invention this is achieved with a cone section warping machine having independent motors for the reed and the deflection roll.